/*
  Copyright (c) 2005, Ulrich Hilger, Light Development, http://www.lightdev.com
  All rights reserved.

  Redistribution and use in source and binary forms, with or without modification, 
  are permitted provided that the following conditions are met:

    - Redistributions of source code must retain the above copyright notice, this 
       list of conditions and the following disclaimer.
       
    - Redistributions in binary form must reproduce the above copyright notice, 
       this list of conditions and the following disclaimer in the documentation 
       and/or other materials provided with the distribution.
       
    - Neither the name of Light Development nor the names of its contributors may be 
       used to endorse or promote products derived from this software without specific 
       prior written permission.

  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 
  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
  SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
  OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 
  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
*/

package primerdb.persistentTree;

/**
 * HierarchicalItem.java
 * 
 * <p>Classes wishing to be treated as part of a hierarchical data structure need to 
 * implement this interface</p>
 * 
 * @author Ulrich Hilger
 * @author Light Development
 * @author <a href="http://www.lightdev.com">http://www.lightdev.com</a>
 * @author <a href="mailto:info@lightdev.com">info@lightdev.com</a>
 * @author published under the terms and conditions of the BSD License,
 *      for details see file license.txt in the distribution package of this software
 *
 * @version 1, 01.08.2005
 */
public interface HierarchicalItem {

  /**
   * set the data of this item
   * @param data  the item's data 
   */
  public void setData(Object data);

  /**
   * get the data of this item
   * @return  the data of this item
   */
  public Object getData();

  /**
   * set the id of this item
   * @param id  the id of this item
   */
  public void setId(Object id);

  /**
   * get the id of this item
   * @return  the id of this item
   */
  public Object getId();

  /**
   * get the id of the parent of this item
   * @return  the id of the parent of this item
   */
  public Object getParentId();

  /**
   * set the id of the parent of this item
   * @param parentId  the parent id of this item
   */
  public void setParentId(Object parentId);

  /**
   * determine if this item is a root item, i.e. has no parent items
   * @return  true if this item is a root item, false otherwise
   */
  public boolean isRoot();

}